public class Example8_4 {
     public static void main(String args[]) {
	double sum=0,item=0;
	boolean computable=true;	
	for(String s:args) {
	   try{ item = Double.parseDouble(s);
		sum=sum+item;
	   }
	   catch(NumberFormatException e) {
		System.out.println("您输入了非数字字符:"+e);
		computable=false;
	    }
	}
	if(computable)
	    System.out.println("sum="+sum);
    }
}
